Hmmm. That's a good question. It can be a bit confusing at time. So you have main roads, for example Sukhumvit. One side of the road has roads labeled with odd number and the other is even, unless there is another main road. So odd would be something like Soi Sukhumvit 49. Then a road off of that could be Soi Sukhumvit 49/11. Houses, well, that is a bit crazy.
Actually, @hirondelle might know more than I do about it.